Confidence: Medium · Source: FCC ULS · As of 2026-09-14
KM4YO callsign genealogy
Currently held by JACKSON JR, HENRY Z
The FCC publishes a previous_call_sign on
every amateur license — a self-link to the licensee's prior callsign.
Following those links produces the chain below.
Previous callsigns
Older callsigns held by KM4YO's current licensee, walking backwards.
- Jackson Jr, Henry ZNCgranted 2024-11-14cancelled 2024-12-03
Successor callsigns
Callsigns held now by people who previously held KM4YO.
No current licensee on record previously held this callsign.
All historical holders
Every license row we've seen with the callsign KM4YO, oldest first.
- JACKSON JR, HENRY Z NC2011-12-02 → cancelled 2023-12-05
- Jackson Jr, Henry Z NC2024-12-03 active